Disclosure: these tools and this post were built with AI assistance by the Blixwerk system and checked automatically.
Some questions come up at the worst possible moment: a client asks for your rate on a call, an invoice is "probably" overdue, a supplier needs an order today, or a CSV export is full of duplicates five minutes before a meeting.
So we put a handful of free, no-signup calculators online. They run entirely in your browser – no tracking, no cookies, nothing is uploaded (the CSV tool reads your file locally).
The tools
- Freelance hourly & day rate calculator – target take-home, business costs, tax set-aside (your own %), weeks off and billable share → minimum hourly rate, day rate and monthly revenue needed.
- Invoice due date & reminder planner – invoice date + terms → due date, days overdue and a polite reminder schedule.
- CSV duplicate finder – pick key columns, see duplicate groups, download a cleaned CSV. Handles
,;and tab, quoted fields, up to 50k rows. - Reorder point & safety stock calculator – daily sales + supplier lead time → reorder point and days of stock left.
- Social media posting schedule generator – platforms × posts per week → an evenly spread calendar you can copy as CSV.
How they're built
Plain vanilla JS, one file per tool, no frameworks, no network calls (fetch, storage and eval are blocked by a build check and by the site's CSP), syntax-checked with node --check before publishing.
Feedback welcome – especially if a result looks wrong for your situation. The numbers are planning aids, not tax or legal guidance.
